Multiplex telegraph



(No Model.)

H. G. NICHOLSON.

Multiplex Telegraph.

No. 238,707. Patented March 8,1881.

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HENRY O. NICHOLSON, OF KENTON, KENTUCKY.

MULTIPLEX TELEGRAPH.

SPECIFICATION forming part of Letters Patent No. 238,707, dated March 8, 1881.

Application filed January 10, 1881. (No model.)

To all whom it may concern:

Be it known that I, HENRY O. NICHOLSON, a citizen of the United States, residing at Kenton, in the county of Kenton and State of Kentucky, have invented certain new and useful Improvements in Multiplex Telegraphs; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawing, and to the letters or figures of reference marked thereon, which forms a part of this specification.

This invention relates to the receiving-instruments of a duplex or multiplex telegraph operating by means of electric currents difiering in polarity and intensity, and at least one of the relays at each station of which is a socalled neutral or ordinary Morse relay, re sponding to currents of determined tension, but of either polarity.

The object of my invention is a means for obviating a kick in the sounder controlled by the neutral relay at times when the armaturelever of said relay may kick back momentarily in consequence of a reversal of the flow of the main-line current.

To this end my invention consists in an insulated contact-spring on the back of the armature-lever, forming one terminal of the local battery, the other terminal of which is formed by a hook on said armature-lever.

The annexed drawing is a diagram of the receiving-instruments at one station of a quadrupleX telegraph, showing the neutral relay in action. One message is received by sounder S, controlled by the polarized relay It, and the other message is received by sounder S controlled by the neutral relay B in manner well known to those skilled in the art. The armature-lever A of the neutral relay is constructed with a hook, a, and a contact-spring, I), is secured to an insulation on the back of said armature-lever, so that its free end may make contact with the hook to. The armaturelever plays between the insulated stops 0 and (Z, its retractile spring a drawing it normally toward the stop 0, which presses the contactspring baway from the hook at, thus breaking the circuit of the local battery. A second insulation may be put on back of armature-lever A to prevent the contact-spring from being forced against the lever under any circumstances.

W'lmnever a sufficiently strong current is put to line the magnet of the neutral relay, by attracting the armature, moves the armaturelever forward to the stop 61, causing the contact-spring b to make contact with hook at, so as to close the circuit of the local battery and make a signal on sounder S Should, during the period of making such a signal, the flow of the main-line current be reversed, the armature-lever of the neutral relay would kick back a little, but not far enough, with proper adjustment of the play of said armature-lever, to break contact between contact-springb and hook a, so that the kick in the relay will pass without causing a kick in the sounder. Hence signals made on sounder S attimes of the reversal of the flow of the main-line current will not be mutilated by the kicks of the armaturelever of the neutral relay. One of the ad vantages of this arrangement is that thelocal circuit, controlled by the neutral relay, is normally open, and is closed when the armaturelever of said relay is attracted by the magnet thereof, in consequence of which the signals, by sounder S are made on the front stroke.

Having thus described my invention, what I claim is-- A neutral relay subject to reversals of the flow of the line-current, the armature-lever of which has a hook, forming one terminal of the local battery, and also carries an insulated coutact-spring, forming the other terminal of said local battery, substantially as before set forth.

In testimony whereof I affix my signature in presence of two witnesses.

HENRY OLAY NICHOLSON.

Witnesses:

A. F. RICHARDSON, J. J. HUME. 

